Electrowetting display devices are known. In an off state of an electrowetting element of an example of such a device an oil layer covers a display area. In an on state the oil layer is retracted so as to cover less of the display area. To switch the element to the on state a voltage is applied via an electrode and an electrically conductive fluid immiscible with the oil. To switch the element to the off state, the voltage is switched off.
It is desirable to provide improvements to an electrowetting element, for example to improve a quality of switching performance.